The present invention relates to disk storage devices. In particular, it is directed to a storage device head-disk enclosure for drives that are servo written with permanent data.
Disk enclosures must be sealed against particulate matter that might be introduced from the surrounding ambient atmosphere. Therefore, the head-disk enclosure is hermetically sealed, sealed with the provision of a breather filter or provided with a continuous supply of filtered air. Rigid disk files also have permanently recorded servo information that must be written on the disk storage surfaces at manufacture. The disk stack of the drive should be accessible from a radial side to enable the servo writing operation to occur without having equipment that might be the source of particulate matter, suspended over the disk data surfaces. A significant portion of the disk stack periphery should be exposed to enable several transducer heads to simultaneously access the disk surfaces, since some servo read-write functions functions must occur concurrently.
Further, the operations that could be accomplished separately or consecutively, would still be accomplished on the most cost effective basis if done simultaneously.
Also, the product heads that will be permanently associated with the disk file should be mounted and operable during the servo write operation. This permits the servo written information to be placed on the data surface with the same departure from radial transducer positioning and transducer skew as the individual transducer head that will function with the particular surface during the life of the product.